[Attention in hyperkinetic children: a signal detection analysis of the effect of methylphenidate]. / Daueraufmerksamkeit bei hyperkinetischen Kindern: Eine Signal-Detection-Analyse der Wirkung von Methylphenidat.

The effects of methylphenidate on sustained attention were investigated in a placebo-controlled double-blind trial with 20 hyperactive boys of normal intelligence with minimal brain dysfunction (MBD). Using signal detection theory methylphenidate significantly increased sensitivity (d) and did not change response bias (beta), independent of the dosage (5 to 20 mg/d). Responders and nonresponders to methylphenidate were differentiated by signal detection analysis: responders improved primarily in sensitivity, whereas nonresponders changed response bias. No response difference was found in physiological and biochemical measures (catecholamines), showing a general activation caused by methylphenidate. It is discussed that methylphenidate is improving information processing and arousal modulation in responders and is raising unspecific activation in nonresponders.

[Benign tumors of the esophagus and stomach]. / Die gutartigen Tumoren des Osophagus und des Magens.

From the tumors of the oesophagus studied, 30% were found to be benign. They occurred in a ratio of 2:1 predominantly in men with an average age of 37,1 years compared to 52,5 years in women. The symptoms were unspecific and the prognosis was quo ad sanationem very good. Only in one case did a neurofibroma relapse explosively with in 4 months and was already inoperable at the time, when the new diagnosis was made. The percent of benign stomach tumors amounted to 2,6%. Tumors of the mucous tissue behaved differently than the neurogenic and mesenchymal ones. The former became noticeable mainly due to epigastric complaints, the latter due to haemorrhages. Epithelial tumors occurred, with a ratio of 2:1, more often in women, but without any difference in age. Mesenchymal and neurogenic tumors occurred in almost the same sex ratio, but at an average age, which was 18 years higher in women. Solitary stomach polypi can mostly be removed endoscopically, whilst all other benign oesophagus and stomach tumors must be removed by operation due to the symptoms and the dignity of the tumor, which is seldom clear.